Improved survival in patients with FDG-PET/CT-based radiotherapy treatment planning for squamous cell anal cancer

The aim of this retrospective analysis was to evaluate the impact of FDG-PET/CT-based target volume definition on locoregional control and survival, compared to conventional CT-based target volume definition and dose prescription. One hundred and twenty-two patients with squamous cell anal cancer were treated with curative radiotherapy (RT) alone (27%) or with RT with concurrent chemotherapy (73%) and analyzed. Forty-six percent had the early disease (stage I+II) and 54% were stage III. FDG-PET/CT-based staging was performed in 21% of the patients. The mean follow-up time was 60 months. Other risk factors affecting survival were investigated. According to initial staging in both groups (FDG-PET/CT and conventional CT) were 10% of stage IV disease, and they were excluded from radical radiotherapy and treated with palliative intent. Ninety-two percent of the patients achieved complete remission. Significant favorable factors in univariate analysis associated with disease-free survival (DFS) were PET/CT staging, T1/2 and N0 stage, and clinical stage I and II. Locoregional control (LRC) correlated with the T1/2 stage and initial performance status (PS) 0. There were no significant factors affecting overall survival (neither in univariate nor multivariate analysis). In multivariate analysis, the factor associated with better DFS was PET/CT staging and for LRC, PS 0 and concomitant chemoradiation. Acute toxicity was increased in the concurrent chemo-radiotherapy group. Two-, five- and ten-year overall survival rates were 83%, 69%, and 60%; disease-free survival rates were 76%, 73%, 73%; local control rates were 91%, 90%, and 90% and colostomy-free survival was 89%, 86%, and 81%, respectively. PET/CT staging allowed targeted dose escalation to the primary tumor and nodal metastases while decreasing dose to uninvolved regions, resulting in significantly improved DFS without compromising locoregional control.

Three-dimensional conformal radiotherapy versus intensity modulated radiotherapy with simultaneous integrated boost in the treatment of locally advanced head and neck carcinoma

The treatment of locally advanced head and neck cancer (LAHNC) requires a multimodality approach. Radiotherapy with combination of chemotherapy are demonstrated to be effective, however, the treatment intensification leads to increased toxicity at the same time. The implementation of three-dimensional conformal radiotherapy (3D-CRT) allowed to irradiate the treatment volume more precisely with better surrounding healthy tissue sparing. Intensity modulated radiotherapy (IMRT) facilitated higher conformity in dose shaping to target volume. IMRT with simultaneous integrated boost (IMRT-SIB) offered the possibility to deliver individualized dose levels within one fraction and enabled escalation of the dose per fraction and radiotherapy acceleration. The aim of our study was to compare the technique of 3D-CRT and IMRT-SIB in the treatment of LAHNC and evaluate the treatment outcome and the treatment-related toxicity. 262 patients in 3D-CRT group and 263 patients in IMRT-SIB group underwent the radical treatment for LAHNC between 1/1998 and 12/2016. No statistically significant differences in locoregional control (LCR) and overall survival (OS) were found between the two groups. Acute toxicity and xerostomia were significantly reduced in the patients treated by IMRT-SIB. IMRT-SIB is a safe radiotherapy method where less toxicity was proven without compromising local control and overall survival.

Scoring systems predictive of survival and local control of patients irradiated for brain metastases

2075

Background: This study was performed to create and validate scoring systems to estimate survival and intracerebral local control at 6 months of patients irradiated for brain metastases. Methods: Data of 1,797 patients irradiated for brain metastases (1,346 whole-brain radiotherapy [WBRT], 131 radiosurgery [RS], 61 WBRT + RS, 259 resection + WBRT) were retrospectively analyzed. Patients were randomly assigned to the test group (N = 1,198) or the validation group (N = 599). In the test group, multivariate analyses (MVA, Cox proportional hazards model) were performed for survival (OS) and local control (LC). Based on the MVA results, two scoring systems were developed, one for OS and another for LC. The scores included the prognostic factors found significant on MVA. Age, performance status, extracranial metastases, interval from tumor diagnosis to RT, and number of brain metastases were significant for OS. Tumor type, performance status, interval from tumor diagnosis to RT, and number of brain metastases were significant for LC. The score for each factor was determined by dividing the 6-month OS or LC rate (%) by 10. The total score represented the sum of the scores for each factor. For OS, total scores ranged from 15–30 points, and patients were divided into three groups (15–19, 20–25, and 26–30 points). For LC, total scores ranged from 14–27 points, and patients were divided into three groups (14–18, 19–23, and 24–27 points). Results: In the test group, the 6-month OS rates were 9 ± 1% for patients with scores of 15–19 points, 41 ± 2% for those with 20–25 points, and 78 ± 2% for those with 26–30 points (p < 0.0001). The corresponding OS rates in the validation group were 7 ± 2%, 39 ± 3%, and 79 ± 3%, respectively (p < 0.0001).In the test group, the 6-month LC rates were 17 ± 3% for patients with 14–18 points, 49 ± 3% for those with 19–23 points, and 77 ± 2% for those with 24–27 points (p < 0.0001). The corresponding LC rates in the validation group were 19 ± 4%, 52 ± 4%, and 77 ± 3%, respectively (p < 0.0001). Conclusions: Patients irradiated for brain metastases can be grouped with these scores to estimate OS and LC. The OS and LC rates of the validation group were almost identical to the test group, which demonstrates the high validity and reproducibility of both scores.

No significant financial relationships to disclose.

Predictors of local failure in early laryngeal cancer

The aim of the study was to assess the impact of factors that could predict the probability of local failure in early laryngeal squamous cell carcinoma treated with curative radiotherapy. Sixty seven patients (12 women and 55 men) with laryngeal cancer stage I (47 patients) and stage II (20 patients) were treated from 1998 to 2003 with curative radiotherapy and retrospectively evaluated. Median follow-up was 36 months (3-80). Local relapse occurred in 10 patients (15%), regional lymphnodes relapse affected 2 patients. The median time between start of radiotherapy to recurrence was 13 months (3-48). Death due to cancer occurred in 4 patients (2 died from locoregional progression of the recurrence and 2 from distant metastases), whereas 7 patients died from non-cancer related causes. The 2-year overall survival rate was 90% and 5-year OS was 79%. The 2-year local control rate was 82% and 5-year local control was 79%. In the univariate analysis there was a statistically significant decrease in local control influenced by grading (p < 0.0001). High risk group of relapse encompassed patients with at least two negative factors: supraglottic tumor, women, radiotherapy prolongation by 3 or more days and high grade tumor and has 3 times worse local control than low risk group (p=0.0125). The highest risk of local recurrence was in the first three years after radiotherapy than later (p=0.0057). On multivariate analysis unfavourable prognostic factors for local control were gender (p=0.022), presence of 2 or more negative risk factors (p=0.018) and lengths of follow up (p=0.005). Radiation dose, stage, age, hemoglobin level and anterior commissure involvement were not significant factors for local control. Overall survival was affected both in the univariate and multivariate analysis by presence of local relapse (p < 0.005) and follow up duration (p < 0.02). Anemia had borderline significance for overall survival in univariate analysis (p=0.064), but in the multivariate analysis was significant unfavourable factor (p=0.008). Other studied factors (radiation dose, anterior commissure involvement and age) were not reaching level of statistical significant value for overall survival. Close follow up strategy is recommended for high risk group of patients with two or more risk factors especially in the first three years after radiation therapy.

Somatic mutations of KIT in familial testicular germ cell tumours

Somatic mutations of the KIT gene have been reported in mast cell diseases and gastrointestinal stromal tumours. Recently, they have also been found in mediastinal and testicular germ cell tumours (TGCTs), particularly in cases with bilateral disease. We screened the KIT coding sequence (except exon 1) for germline mutations in 240 pedigrees with two or more cases of TGCT. No germline mutations were found. Exons 10, 11 and 17 of KIT were examined for somatic mutations in 123 TGCT from 93 multiple-case testicular cancer families. Five somatic mutations were identified; four were missense amino-acid substitutions in exon 17 and one was a 12 bp in-frame deletion in exon 11. Two of seven TGCT from cases with bilateral disease carried KIT mutations compared with three out of 116 unilateral cases (P=0.026). The results indicate that somatic KIT mutations are implicated in the development of a minority of familial as well as sporadic TGCT. They also lend support to the hypothesis that KIT mutations primarily take place during embryogenesis such that primordial germ cells with KIT mutations are distributed to both testes.